the Role of Hsp70 in the transcription regulation of Maltase in Saccharomyces cerevisiae
......................................................................................................... SSA-type Hsp70 Complex Chime Image ( you need to install the chime image in your computer) All organisms respond to heat by inducing the synthesis of a group of proteins called the heat-shock proteins or hsps. These proteins are among the most highly conserved proteins in existence. In the earlier peirild of the research, the hsp is supposed to play a vital role in thermotolerane. But, it is still not so clear that what specific role they have on the genetic regulation and metablism. Cn3D image Chain A-Cn3D image Chain B-Cn3D image Protein Structural Classification in : 1. SCOP 2. CATH the Saccharomyces cerevisiae genome contains at least nine genes related to HSP70 of higher eucaryotes. Eight of these genes, originally named YG100-YG107, have been renamed on the basis of structural and functional similarities: SSA1-4; SSB1 and SSB2; SSC1; adn SSD1. Recently, another member of this family, the KAR2 gene has been identified. The sequence relationships among these gens are complex, with nucleotide identities ranging from50-96%. . SEQUENCE AND SECONDARY STRUCTURE VAST STRUCTURE NEIGHBORS: SSA3 and SS4 are expressed at very low levels during steady-state growth at 23oC, but their expression is greatly enhanced upon upshift to 39oC. SSA2 expression changes little upon shift to a higher or lower temperature. Strains containing mutatins in SSA4, SSA3 or SSA4 and SSA3 were found to be indistinguished from wild-type; However, ssa1 ssa2 ssa4 strains are not viable spores of this genotype do not bud and vegetatively growing cells containing a SSA1 gen under the control of a conditionall protmoter undergo.The mutants ssa1ssa2 strain are temperature sensitive for growth; they grow at 23oC but are unable to form colonies at 37oC. The reaon for the inability of SSA4 and SSA3 to allow growth at 37oC in the absence of SA1 and SSA2 is not clear. SSA3 and SSA2 are functionally different or predominately in a defferent cellular location from SSA1 and SSA2 proteins. the Phylogenetic Tree analysis of the S.cerevisiae ssa1p's relationship with its homologous proteins ANIMATION OF THE CRYSTAL STRUCTURE DIFFERENCE FROM OTHER HOMOLOGOUS: IMITATION OF THE LIGAND DOCKING ON THE PROTEIN WITH tRNA INSTEAD OF DNA In Saccharomyces cerevisiae, the Hsp70 (Heat Shock Protein with a moleculor mass of 70 KDal) plays a very important role in the physiological regulation of the gene express. According to the report from Dr. Zhang, the Hsp70 molecular chaperone represses the activity of the Heme activator protein Hap1 in the absence of heme, In my project, we try to detect the effects of this protein on the maltase gene regulatory system. For the wild type strain, maltase activator protein is bound by some other proteins, we call them mediator, we suspect that Hsp70 is also involved in action of mediator, when the inducer-maltose was added into culture, it can release the activator protein from the mediator, we expect to find that the mutant strain which is lack of Hsp70 can synthesize the maltase without inducer maltose. It will turn out to be that the Hsp70 is a essential part of mediator protein. Comparation of the homologous sequences between yeast ssa1p and heat shock protein72 3D-STEREO ANIMATION FOR THE 6 STRUCTURES OF THE HOMOLOGOUS PROTEINS OF THE HSP70 CHAIN A (please use the special glasses for the 3D-stereo image) the helical wheel (right image) components of a part of this structure, which has been labeled by the yellow color (left image). the sequence of this helix also been shown in the left. THE ROTATION ANIMATION OF THE 3D-STEREO STRUCTURE OF HSP70 CHAIN A (please use the special glasses for the 3D-stereo image) the Titration Curve of the protein ssa-type Hsp70 THE CONSERVED DOMAIN ARCHITECTURE OF SSA-TYPE HSP70 PROTEIN REFERENCE AND TOOLS go home
All organisms respond to heat by inducing the synthesis of a group of proteins called the heat-shock proteins or hsps. These proteins are among the most highly conserved proteins in existence. In the earlier peirild of the research, the hsp is supposed to play a vital role in thermotolerane. But, it is still not so clear that what specific role they have on the genetic regulation and metablism.
the Saccharomyces cerevisiae genome contains at least nine genes related to HSP70 of higher eucaryotes. Eight of these genes, originally named YG100-YG107, have been renamed on the basis of structural and functional similarities: SSA1-4; SSB1 and SSB2; SSC1; adn SSD1. Recently, another member of this family, the KAR2 gene has been identified. The sequence relationships among these gens are complex, with nucleotide identities ranging from50-96%. . SEQUENCE AND SECONDARY STRUCTURE
VAST STRUCTURE NEIGHBORS:
SSA3 and SS4 are expressed at very low levels during steady-state growth at 23oC, but their expression is greatly enhanced upon upshift to 39oC. SSA2 expression changes little upon shift to a higher or lower temperature. Strains containing mutatins in SSA4, SSA3 or SSA4 and SSA3 were found to be indistinguished from wild-type; However, ssa1 ssa2 ssa4 strains are not viable spores of this genotype do not bud and vegetatively growing cells containing a SSA1 gen under the control of a conditionall protmoter undergo.The mutants ssa1ssa2 strain are temperature sensitive for growth; they grow at 23oC but are unable to form colonies at 37oC. The reaon for the inability of SSA4 and SSA3 to allow growth at 37oC in the absence of SA1 and SSA2 is not clear. SSA3 and SSA2 are functionally different or predominately in a defferent cellular location from SSA1 and SSA2 proteins.
ANIMATION OF THE CRYSTAL STRUCTURE DIFFERENCE FROM OTHER HOMOLOGOUS:
IMITATION OF THE LIGAND DOCKING ON THE PROTEIN WITH tRNA INSTEAD OF DNA
In Saccharomyces cerevisiae, the Hsp70 (Heat Shock Protein with a moleculor mass of 70 KDal) plays a very important role in the physiological regulation of the gene express. According to the report from Dr. Zhang, the Hsp70 molecular chaperone represses the activity of the Heme activator protein Hap1 in the absence of heme, In my project, we try to detect the effects of this protein on the maltase gene regulatory system. For the wild type strain, maltase activator protein is bound by some other proteins, we call them mediator, we suspect that Hsp70 is also involved in action of mediator, when the inducer-maltose was added into culture, it can release the activator protein from the mediator, we expect to find that the mutant strain which is lack of Hsp70 can synthesize the maltase without inducer maltose. It will turn out to be that the Hsp70 is a essential part of mediator protein.
3D-STEREO ANIMATION FOR THE 6 STRUCTURES OF THE HOMOLOGOUS PROTEINS OF THE HSP70 CHAIN A (please use the special glasses for the 3D-stereo image)
THE ROTATION ANIMATION OF THE 3D-STEREO STRUCTURE OF HSP70 CHAIN A (please use the special glasses for the 3D-stereo image)
THE CONSERVED DOMAIN ARCHITECTURE OF SSA-TYPE HSP70 PROTEIN
REFERENCE AND TOOLS
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